Finally! After all of the requests, I've decided to put together a list of FAQ's regarding transportation from one place to another (from the airport to WDW, for example, or from WDW to Universal, etc.). This is a work in progress, so please feel free to reply to this topic with any ideas that you think should be included. Enjoy! 
IMPORTANT NOTE: All information provided herein is for informational purposes only, and may not be the most up-to-date information. It is your responsibility to check the accuracy of the statements provided with each company with the company itself and make sure you know exactly what you are agreeing to. In other words, no WHINING!
WHAT ARE ALL THE TRANSPORTATION COMPANIES?
If you know of one to add to the list, please PM it to me, and if applicable, send me the link to its website. (Moderators, please feel free to edit as necessary)
Shuttle Service
Mears Transportation Group
Towncar/Limo/Van Service (in alphabetical order)
Cartier Towncars Cartier Towncar Rates
Fare includes everything except gratuity (minimum 20%). Fare includes 20 minute grocery stop.
FL Tours- DIS SPONSOR (Use the links at the very top of this page)
Fare includes everything except gratuity (no minimum, but $10-15 suggested). Unlimited free carseats/boosters. Fare includes 30 minute grocery stop.
Happy Limo Happy Limo Rates
-NOTE, Happy Limo charge extra fees for Pickup from MCO or SFD, round trips to/from MK resorts (CR, Poly, WL, FW, SoG, GF), international arrivals, carseats/boosters. They also charge a mandatory 20% gratuity. Fares include 15 minute grocery stop.
Murray Hill Transportation (Rates listed on homepage)
Rates include everything except gratuity and more than one carseat/booster. Rates include 30 minute grocery stop.
Quicksilver Transportation Quicksilver Transportation Rates
Rates include everything except gratuity (no minimum for towncar service, mandatory 20% for limos). Rates include 30 minute grocery stop and a free 10 minute local/long distance or 5 minute international cell-phone call.
Prestige Towncar (Rates listed on homepage)
Rates include everything except MAYBE gratuity (gratuity information not listed on website). Rates include 30 minute grocery stop.
Selective Limousine Selective Limousine Rates
Rates include everything except WDW gate fee and gratuity (mandatory 20%). Includes grocery stop (length unknown).
Tiffany Towncars Tiffany Towncar Rates
Nothing mentioned on website as to what is included in rates. It has been reported on the DIS that they include a grocery stop (unknown length) and a carseat/booster, but to be sure, check with the company. Gratuity is probably NOT included in rates.
Now, for that eternal question:
DO I CHOOSE A TOWNCAR SERVICE OR THE MEARS SHUTTLE?
Answer: If you are looking at making the absolute cheapest vacation possible, and your party is 3 people or less, then go with the Mears shuttle if it works out to be cheaper than any of the towncar options. While there are plenty of both good and bad stories about Mears, they are usually fairly reliable and problems are few and far between.
That said, the consensus from members of the DIS is this: IF you can afford the towncar, then definitely go with the towncar. Lots of people see the value in having the personalized service and not having to share your vehicle with people you don't know. Just like the old addage, "You get what you pay for." Plus, if your party is 4 or more people, a towncar might actually be cheaper in the long run! One certain thing is that your commute from the airport to your resort would be about an hour longer by taking the Mears shuttle than it would be to hire a towncar/limo service.
Another way to look at it is this: for the most part, you probably want your trip to Disney (or USO, etc.) to be a special one. Why not add to that special feeling by including a personalized, private ride to your resort? This is something that is just not possible using the Mears shuttle.
HOW MUCH DO I TIP A LIMO/TOWNCAR DRIVER?
Here's a thread discussing this
OKAY, I'VE DECIDED THAT I WANT TO HIRE A TOWNCAR/LIMO. WHICH COMPANY DO I CHOOSE?
Answer: There is no easy answer. You have to factor in price and reviews of the company into your decision. For the most part, you probably will not be disappointed by any of the companies' services. However, if you want your service to go above and beyond, only certain companies will do that.
Here's a recent poll of DIS'ers telling which company they would choose
And here's a poll of people that had BAD experiences with one company or another.
I'VE HEARD OTHERS MENTION A GROCERY STOP. WHAT IS THIS AND WHY WOULD I WANT IT?
Answer: WDW is certainly not run by morons. They know that if you arrive for your vacation and you need to need purchase any necessities such as food/drink for your hotel room, toiletries, etc., you will pay top dollar for these items, thereby saving the money and hassle to take a taxi or other form of transportation out to a grocery or drug store.
Most, if not all, of the towncar companies offer a "free grocery stop" for all of their paying clients, allowing you to shop for supplies at Publix, Goodings, or Winn Dixie on your way to your resort (certain companies may limit which store you go to, others may give you your choice, check with the company). If the company includes this grocery stop as part of their service, they will probably mention it on their website, however it has been confirmed that Tiffany Towncars does offer a stop, even though there is no mention of it on their website.
It is highly advised that you take advantage of this grocery stop to pick up snacks, drinks, and supplies, rather than purchasing them at the hotel directly. You will save a lot of money and agony in the long run.
IMPORTANT NOTE: All information provided herein is for informational purposes only, and may not be the most up-to-date information. It is your responsibility to check the accuracy of the statements provided with each company with the company itself and make sure you know exactly what you are agreeing to. In other words, no WHINING!
WHAT ARE ALL THE TRANSPORTATION COMPANIES?
If you know of one to add to the list, please PM it to me, and if applicable, send me the link to its website. (Moderators, please feel free to edit as necessary)
Shuttle Service
Mears Transportation Group
Towncar/Limo/Van Service (in alphabetical order)
Cartier Towncars Cartier Towncar Rates
Fare includes everything except gratuity (minimum 20%). Fare includes 20 minute grocery stop.
FL Tours- DIS SPONSOR (Use the links at the very top of this page)
Fare includes everything except gratuity (no minimum, but $10-15 suggested). Unlimited free carseats/boosters. Fare includes 30 minute grocery stop.
Happy Limo Happy Limo Rates
-NOTE, Happy Limo charge extra fees for Pickup from MCO or SFD, round trips to/from MK resorts (CR, Poly, WL, FW, SoG, GF), international arrivals, carseats/boosters. They also charge a mandatory 20% gratuity. Fares include 15 minute grocery stop.
Murray Hill Transportation (Rates listed on homepage)
Rates include everything except gratuity and more than one carseat/booster. Rates include 30 minute grocery stop.
Quicksilver Transportation Quicksilver Transportation Rates
Rates include everything except gratuity (no minimum for towncar service, mandatory 20% for limos). Rates include 30 minute grocery stop and a free 10 minute local/long distance or 5 minute international cell-phone call.
Prestige Towncar (Rates listed on homepage)
Rates include everything except MAYBE gratuity (gratuity information not listed on website). Rates include 30 minute grocery stop.
Selective Limousine Selective Limousine Rates
Rates include everything except WDW gate fee and gratuity (mandatory 20%). Includes grocery stop (length unknown).
Tiffany Towncars Tiffany Towncar Rates
Nothing mentioned on website as to what is included in rates. It has been reported on the DIS that they include a grocery stop (unknown length) and a carseat/booster, but to be sure, check with the company. Gratuity is probably NOT included in rates.
Now, for that eternal question:
DO I CHOOSE A TOWNCAR SERVICE OR THE MEARS SHUTTLE?
Answer: If you are looking at making the absolute cheapest vacation possible, and your party is 3 people or less, then go with the Mears shuttle if it works out to be cheaper than any of the towncar options. While there are plenty of both good and bad stories about Mears, they are usually fairly reliable and problems are few and far between.
That said, the consensus from members of the DIS is this: IF you can afford the towncar, then definitely go with the towncar. Lots of people see the value in having the personalized service and not having to share your vehicle with people you don't know. Just like the old addage, "You get what you pay for." Plus, if your party is 4 or more people, a towncar might actually be cheaper in the long run! One certain thing is that your commute from the airport to your resort would be about an hour longer by taking the Mears shuttle than it would be to hire a towncar/limo service.
Another way to look at it is this: for the most part, you probably want your trip to Disney (or USO, etc.) to be a special one. Why not add to that special feeling by including a personalized, private ride to your resort? This is something that is just not possible using the Mears shuttle.
HOW MUCH DO I TIP A LIMO/TOWNCAR DRIVER?
Here's a thread discussing this
OKAY, I'VE DECIDED THAT I WANT TO HIRE A TOWNCAR/LIMO. WHICH COMPANY DO I CHOOSE?
Answer: There is no easy answer. You have to factor in price and reviews of the company into your decision. For the most part, you probably will not be disappointed by any of the companies' services. However, if you want your service to go above and beyond, only certain companies will do that.
Here's a recent poll of DIS'ers telling which company they would choose
And here's a poll of people that had BAD experiences with one company or another.
I'VE HEARD OTHERS MENTION A GROCERY STOP. WHAT IS THIS AND WHY WOULD I WANT IT?
Answer: WDW is certainly not run by morons. They know that if you arrive for your vacation and you need to need purchase any necessities such as food/drink for your hotel room, toiletries, etc., you will pay top dollar for these items, thereby saving the money and hassle to take a taxi or other form of transportation out to a grocery or drug store.
Most, if not all, of the towncar companies offer a "free grocery stop" for all of their paying clients, allowing you to shop for supplies at Publix, Goodings, or Winn Dixie on your way to your resort (certain companies may limit which store you go to, others may give you your choice, check with the company). If the company includes this grocery stop as part of their service, they will probably mention it on their website, however it has been confirmed that Tiffany Towncars does offer a stop, even though there is no mention of it on their website.
It is highly advised that you take advantage of this grocery stop to pick up snacks, drinks, and supplies, rather than purchasing them at the hotel directly. You will save a lot of money and agony in the long run.
)
